JP3035744B2 - Swing type anhydrous hammer check valve - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a swing type anhydrous type installed in a pipeline for transferring a fluid to prevent a backflow of the fluid and to safely and surely prevent a water hammer action due to the backflow of the fluid. It relates to a fire check valve. In the present specification, the term “water” generically represents a fluid.

2. Description of the Related Art In a conventional swing type water hammer check valve, a valve body is closed without delay in response to a flow of a fluid, and a valve closing force of a valve body relative to a valve opening force generated by the flow of a fluid. It is well known to use the biasing force of a spring having one end fixed to a valve body and the other end fixed to a valve box in order to obtain.

When using the spring as a biasing force for closing the valve, if the spring force of a structure in which one end is simply fixed to the valve body and the other end is fixed to the valve box as conventionally used, the compression of the spring or Regardless of the "torsion" force, the spring force is weakest when the valve is fully closed, and the spring force increases linearly as the valve is opened. On the other hand, in order to fully demonstrate the performance of the water-free hammer check valve, which eliminates the valve closing delay and prevents the occurrence of water hammer due to backflow, the valve generated by the fluid flow when the valve is fully open is required. It is desirable to obtain a spring force enough to obtain the valve closing force of the valve body balanced with the valve force, and also to obtain a sufficient valve closing force (sealing force) even near the fully closed state. It is desirable to have a structure in which the spring force changes little with respect to the valve opening.
As long as a spring structure in which one end is fixed to the valve body and the other end is fixed to the valve box, adjustment of the spring force is limited, and assembly is difficult.

The present invention has a simple and easy-to-assemble structure in which the shape of the spring, the holding method and the adjustment method of the spring force are appropriately adjusted, so that the valve closing force capable of responding to the flow change and the sealing force at the time of full closing can be obtained. It is an object of the present invention to provide a high performance and economical water-free hammer check valve which can be held, prevent the components from being worn, and be economical.

DISCLOSURE OF THE INVENTION In order to achieve the above-mentioned object, a swing type anhydrous hammer check valve according to the present invention includes a valve seat having a fluid inlet and an outlet, a valve seat, a valve shaft, and a swing rotation performed on the valve shaft. In a swing check valve provided with a freely mounted valve element and a spring for energizing a valve closing force provided on the valve shaft, the spring is wound right and left in opposite directions around a substantially central portion. A detachable pin is mounted at a substantially central portion on the valve shaft, and the valve shaft is rotated by a predetermined amount while the pin is pressed against a substantially central portion of the spring. By being fixed to the valve box after being made, both ends of the spring are both pressed against the symmetrical portion of the valve body in the valve closing direction, so that the structure is configured to urge the valve closing force. It is characterized by. This simple and rational structure makes it easy to design, assemble, adjust and disassemble, improves economics, and minimizes the difference in spring force between fully closed and fully open. Further, it is possible to easily obtain a valve closing force that is sufficient to prevent water hammer, and a high degree of tightness of the valve body can be easily obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view (partially sectional view) showing an embodiment of the present invention.

FIG. 2 is a sectional view of a main part around the valve shaft in FIG.

FIG. 3 is a perspective view (partially sectional view) showing another embodiment of the present invention.

FIG. 4 is a sectional view of a main part around the valve shaft in FIG.

FIG. 5 is a sectional view showing various embodiments of the notch of the valve shaft.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described with reference to FIGS. 1 and 2 showing one embodiment.

1 and 2, a valve body 2 that can freely rotate with respect to a valve shaft 3 and a spring 4 that is wound in the left and right directions around a substantially central portion as shown in FIG. 1 through a valve shaft 3 and a detachable set pin 5
Is attached to the valve shaft 3, and the valve shaft 3 is rotated to set the set pin 5
Against the substantially central portion of the spring 4, and further, until both ends of the spring 4, which are pressed at substantially symmetric positions of the valve body 2, apply a predetermined closing force to the valve body 2.
Is rotated, the valve shaft 3 is fixed in the rotational direction by a notch provided at the shaft end of the valve shaft 3 and the knock pin 6 mounted on the valve box 1 to prevent rotation, and the bearing of the valve box 1 is further stopped. The screw plugs 7a and 7b tightened from the left and right of the part maintain the positioning of the valve shaft end and maintain the sealing performance.

By appropriately setting the relative angle between the notch provided on the end face of the valve shaft 3 and the mounting hole for the set pin 5, the force for pressing the valve body 2 against the valve seat 1a provided on the valve box 1 and the valve body 2, the valve closing force at the time of full opening is adjustable. Further, since the acting force of the spring 4 is applied symmetrically in the axial direction of the valve shaft 3 and always to the left and right with the set pin 5 as a fulcrum as shown in FIG. Cut-off hardly occurs. In addition, the rotational movement of the valve element 2 is stable without twisting.

A notch for facilitating the rotation operation of the valve shaft 3 when adjusting the preload of the spring 4 is provided on a shaft end used for preventing rotation of the valve shaft 3 in the rotation direction or on the opposite shaft end. Is provided.

3 and 4 show an embodiment in which the structure around the valve shaft is further simplified. This uses an O-ring groove additionally processed at the position closest to the fluid flow path of the valve shaft 3, and regulates both the rotation direction and the axial direction by the knock pin 6,
This is a structure in which a seal is obtained by the ring 8. According to this structure, the knock pin 6 located outside the O-ring 8,
The sealing of the screw plugs 7a; 7b is not required, and the screw plugs 7a; 7b themselves can be omitted as shown in FIGS.

As illustrated in FIG. 5, the shape of the notch at the shaft end of the valve shaft 3 and the structure of the detent may be a semicircular shape, a polygonal shape, or a pin hole / slit groove shape. Various types of knock pins 6 can be used. Valve shaft 3
In order to prevent the rotation of the valve, the knock pin 6 is attached to the valve box 1 in advance, and the set pin 5 is
And pushes the valve shaft 3 in the axial direction while rotating the valve shaft 3 to fit a notch in the knock pin 6 (in this case, the valve shaft 3
The notches are as illustrated in a to e in FIG. 5)
And a method in which the valve shaft 3 is inserted to a predetermined axial position and then rotated and fixed with the knock pin 6. Further, depending on the combination of the shape of the notch and the knock pin 6, not only the rotation direction of the valve shaft 3 but also the axial position can be restricted at the same time.

The same applies to the notch for the valve shaft rotation operation.
As illustrated in FIGS. A to e, any shape corresponding to the jig for the rotation operation (in which the unevenness is set to be reversed) can be applied.

At the time of disassembly, the spring force is released by removing the knock pin 6, then the set pin 5 is removed, and the valve body 2 and the valve shaft 3 may be disassembled, so that the work can be carried out lightly. It is of course possible to release the spring force by pulling out the set pin 5.

Regarding the shapes of the valve body 2 and the valve seat 1a, a perfect circle, an ellipse,
Oval type etc. can be used, and regarding the position of the valve seat 1a,
It can be set concentric with the center of the valve box 1, set eccentrically, or set inclined with respect to the flow path line. Further, in order to enhance the sealing performance of the valve body 2, the valve body 2 may be divided into two sections, a valve section and an arm section. valve seat
As the sealing means for sealing the valve body 2 with respect to 1a, various types such as an O-ring, a gasket, a baked rubber material, and a metal touch can be used.

The set pin 5 and the knock pin 6 may have various forms such as a rod, a split pin, and a screw.

Since the structure of the present invention is simple, even in a flange type check valve, a so-called wafer type check valve,
Further, the present invention can be applied to a gas damper or the like. It is also possible to provide a bypass valve between the inlet and the outlet.
Further, when the flow path conditions are complicated, a dashpot or the like for reducing the closing impact of the valve body may be provided.

In the present embodiment, a coil type torsion spring is taken as an example of the urging spring of the valve body, but a plate-shaped spring may be used. In any case, it is needless to say that it is desirable to use a spring having a spring constant as low as possible. When a stronger spring force is required, a conventional spring having a structure in which one end is fixed to a valve body and the other end is fixed to a valve box is provided along the outer periphery or outside of the spring of the present invention. However, it is also possible to use the resultant force of both springs.

In addition, the design, such as the arrangement (positional relationship) and combination of the spring, the valve shaft, the valve body, and the like, can be changed within the intended range of the present invention, and the present invention is not limited to the above embodiment.

INDUSTRIAL APPLICABILITY According to the swing type anhydrous hammer check valve of the present invention, the number of parts is small due to a very simple structure, disassembly / assembly is possible with the spring released, and work is easy and safe. In addition, the valve closing force of the valve body, which balances the pressing force of the valve body against the valve seat and the valve opening force generated by the flow of the fluid, can be arbitrarily adjusted and set. In addition, since the spring is pre-loaded after the valve is assembled, the same effect as mounting a fully compressed spring is obtained.Therefore, there is no need to install a spring with a large spring force from the beginning. And the difference in spring force when the valve is fully opened can be minimized, so that the valve can be quickly closed and the valve can be easily sealed sufficiently to prevent water hammer. Since the manner in which the spring acting force is applied is balanced in the axial direction (left and right), the wear of each member is small, and the economic effect is large.

With the above effects, great results can be achieved in all fields that require check valves.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16K 15/03 F16K 47/02

Claims (1)

(57) [Claims] 1. A valve seat having a fluid inlet and an outlet, a valve seat, a valve shaft, a valve body swingably mounted on the valve shaft, and a valve closing force provided on the valve shaft. In a swing type check valve provided with a biasing spring, the spring is formed of a single spring wound in a left-right opposite direction with a substantially central portion as a boundary. A detachable pin is mounted, and while the pin is pressed against a substantially central portion of the spring, the valve shaft is rotated by a predetermined amount and then fixed to the valve box. Are both pressed against a symmetrical portion of the valve body in a valve closing direction to apply a valve closing force.